No. You need to wait until you either have the urge to push and are in labor, or you need to wait until you are 9 cm or 10 cm. If you start pushing now nothing will probably happen execpt bad hemmroids and possibly making the baby go into distress. The baby will not fit through 3 cm, especially if it's at normal weight which should be 7-9 lbs. You need to just wait until you go into labor, don't rush things, that's not good for your body or your baby, just let it happen the way it's suppose to.

You can't just push and a baby is going to come out anyways if you did don't you think it would hurt even worse pushing out that big head through a small opening. You need to just relax and wait for it to happen.

No, you have to be fully dilated, (10 cm) before it is safe to push the baby out.